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development. As the temporal and spatial scales of interest become smaller, many more instabilities and processes are known to play a significant role, at least intermittently, in the evolution of the atmosphere at a given location. The skill of numerical models in predicting the variety of mesoscale and small-scale phenomena is not well known, since our ability to observe these phenomena is limited. However, if one examines summertime quantitative precipitation forecasts associated with mesoscale
development. As the temporal and spatial scales of interest become smaller, many more instabilities and processes are known to play a significant role, at least intermittently, in the evolution of the atmosphere at a given location. The skill of numerical models in predicting the variety of mesoscale and small-scale phenomena is not well known, since our ability to observe these phenomena is limited. However, if one examines summertime quantitative precipitation forecasts associated with mesoscale
VOL. I10, NO. 3 MONTHLY WEATHER REVIEW MARCH 1982Synoptic-Scale and Mesoscale Contributions to Objective Operational Maximum Minimum Temperature Forecast Errors DENNIS G. BAKERDepartment of Atmospheric and Oceanic Science, University of Michigan. Ann Arbor 48109(Manuscript received 13 July 1981, in final form 30 December 1981 ) ABSTRACT Root-mean-square errors of the
VOL. I10, NO. 3 MONTHLY WEATHER REVIEW MARCH 1982Synoptic-Scale and Mesoscale Contributions to Objective Operational Maximum Minimum Temperature Forecast Errors DENNIS G. BAKERDepartment of Atmospheric and Oceanic Science, University of Michigan. Ann Arbor 48109(Manuscript received 13 July 1981, in final form 30 December 1981 ) ABSTRACT Root-mean-square errors of the
120 WEATHER AND FORECASTING VOLUME?FORECASTER'S FORUMOn the Use of Mesoscale and Cloud-Scale Models in Operational ForecastingHAROLD E. BROOKS, CHARLES A. BOSWELL III, AND ROBERT A. MADDOXNOAA /National Severe Storms Laboratory, Norman, Oklahoma27 August 1991 and 8 November 1991 In the near future, the technological capability will be available to use mesoscale and cloud
120 WEATHER AND FORECASTING VOLUME?FORECASTER'S FORUMOn the Use of Mesoscale and Cloud-Scale Models in Operational ForecastingHAROLD E. BROOKS, CHARLES A. BOSWELL III, AND ROBERT A. MADDOXNOAA /National Severe Storms Laboratory, Norman, Oklahoma27 August 1991 and 8 November 1991 In the near future, the technological capability will be available to use mesoscale and cloud
the assimilation cycles or assimilation window, a final analysis is produced that provides the initial condition for a subsequent model forecast. When the initial condition is based on an analysis at a single time, and especially when the analysis background is from the forecast of a different model, the subsequent forecast is often referred to as “cold starting” from such initial conditions. No matter how the initial conditions are derived, for mesoscale and storm-scale NWP, they should contain
the assimilation cycles or assimilation window, a final analysis is produced that provides the initial condition for a subsequent model forecast. When the initial condition is based on an analysis at a single time, and especially when the analysis background is from the forecast of a different model, the subsequent forecast is often referred to as “cold starting” from such initial conditions. No matter how the initial conditions are derived, for mesoscale and storm-scale NWP, they should contain
LAPS within the OWSS was important. For the first time, a mesoscale forecast model initialized with comparably high-resolution analyses was implemented in an operational environment using technology representative of that planned for NWS forecast offices in the next several years. The LAPS forecasts were produced by the Regional Atmospheric Modeling System (RAMS) ( Pielke et al. 1992 ; Walko et al. 1995 ) developed at Colorado State University. The operational forecaster interactively selected
LAPS within the OWSS was important. For the first time, a mesoscale forecast model initialized with comparably high-resolution analyses was implemented in an operational environment using technology representative of that planned for NWS forecast offices in the next several years. The LAPS forecasts were produced by the Regional Atmospheric Modeling System (RAMS) ( Pielke et al. 1992 ; Walko et al. 1995 ) developed at Colorado State University. The operational forecaster interactively selected
1. Introduction Extreme precipitation, and the flooding and flash flooding it can cause, remains a particularly challenging prediction problem for numerical models and human forecasters (e.g., Fritsch and Carbone 2004 ; Novak et al. 2011 ). This stems in part from the small-scale, chaotic nature of the deep convection that is responsible for producing the heavy rainfall (e.g., Zhang et al. 2003 ) and the insufficient density of observations at the mesoscale (e.g., Dabberdt et al. 2005
1. Introduction Extreme precipitation, and the flooding and flash flooding it can cause, remains a particularly challenging prediction problem for numerical models and human forecasters (e.g., Fritsch and Carbone 2004 ; Novak et al. 2011 ). This stems in part from the small-scale, chaotic nature of the deep convection that is responsible for producing the heavy rainfall (e.g., Zhang et al. 2003 ) and the insufficient density of observations at the mesoscale (e.g., Dabberdt et al. 2005
forecasts for Europe . Bull. Amer. Meteor. Soc. , 94 , 1393 – 1405 , https://doi.org/10.1175/BAMS-D-12-00099.1 . 10.1175/BAMS-D-12-00099.1 Rutledge , S. A. , and P. V. Hobbs , 1983 : The mesoscale and microscale structure of organization of clouds and precipitation in midlatitude cyclones. VIII: A model for the “seeder-feeder” process in warm-frontal rainbands . J. Atmos. Sci. , 40 , 1185 – 1206 , https://doi.org/10.1175/1520-0469(1983)040<1185:TMAMSA>2.0.CO;2 . 10
forecasts for Europe . Bull. Amer. Meteor. Soc. , 94 , 1393 – 1405 , https://doi.org/10.1175/BAMS-D-12-00099.1 . 10.1175/BAMS-D-12-00099.1 Rutledge , S. A. , and P. V. Hobbs , 1983 : The mesoscale and microscale structure of organization of clouds and precipitation in midlatitude cyclones. VIII: A model for the “seeder-feeder” process in warm-frontal rainbands . J. Atmos. Sci. , 40 , 1185 – 1206 , https://doi.org/10.1175/1520-0469(1983)040<1185:TMAMSA>2.0.CO;2 . 10
) and Mesoscale Eta Models (MESO; Black 1994 ), the National Center for Environmental Prediction’s (NCEP’s) most complex synoptic model and first mesoscale model, respectively, produce high-resolution output at 30–50 vertical levels and at every forecast hour in the form of soundings (or“profiles”). Therefore, the fine time and spatial resolutions of the model output make possible operational prediction of mesoscale features unlike what has been possible previously. The forecasting problem is how
) and Mesoscale Eta Models (MESO; Black 1994 ), the National Center for Environmental Prediction’s (NCEP’s) most complex synoptic model and first mesoscale model, respectively, produce high-resolution output at 30–50 vertical levels and at every forecast hour in the form of soundings (or“profiles”). Therefore, the fine time and spatial resolutions of the model output make possible operational prediction of mesoscale features unlike what has been possible previously. The forecasting problem is how
1996 ; Marchok et al. 2007 ), or African easterly waves ( Céron and Guérémy 1999 ) are essential to accurate QPFs over the specific regions. Examining numerical forecasts of MPs is important so that additional contributions to QPF errors for progressive MCSs can be identified. The purpose of this study is to evaluate the forecasts of MPs and their associated rainfall in the National Centers for Environmental Prediction’s (NCEP’s) operational North American Mesoscale (NAM) model. Evaluation of
1996 ; Marchok et al. 2007 ), or African easterly waves ( Céron and Guérémy 1999 ) are essential to accurate QPFs over the specific regions. Examining numerical forecasts of MPs is important so that additional contributions to QPF errors for progressive MCSs can be identified. The purpose of this study is to evaluate the forecasts of MPs and their associated rainfall in the National Centers for Environmental Prediction’s (NCEP’s) operational North American Mesoscale (NAM) model. Evaluation of
acknowledge Mike Baldwin, Barbara Brown, Chris Davis, and Randy Bullock for contributing to all levels of this project. Partial support for this project was provided by the Weather Research and Forecasting Model Developmental Testbed Center (WRF/DTC), and by the National Science Foundation Grant 0513871. REFERENCES Baldwin , M. E. , S. Lakshmivarahan , and J. S. Kain , 2001 : Verification of mesoscale features in NWP models. Preprints, Ninth Conf. on Mesoscale Processes, Fort Lauderdale, FL
acknowledge Mike Baldwin, Barbara Brown, Chris Davis, and Randy Bullock for contributing to all levels of this project. Partial support for this project was provided by the Weather Research and Forecasting Model Developmental Testbed Center (WRF/DTC), and by the National Science Foundation Grant 0513871. REFERENCES Baldwin , M. E. , S. Lakshmivarahan , and J. S. Kain , 2001 : Verification of mesoscale features in NWP models. Preprints, Ninth Conf. on Mesoscale Processes, Fort Lauderdale, FL
